Add HTTP 400 Bad Request as a possible generic error response (#1165)

Author: arttuperala

CHANGELOG.md

@@ -14,6 +14,7 @@ any parts of the framework not mentioned in the documentation should generally b
 
 * Added support for Python 3.11.
 * Added support for Django 4.2.
+* Added `400 Bad Request` as a possible error response in the OpenAPI schema.
 
 ### Changed
 

example/tests/__snapshots__/test_openapi.ambr

@@ -38,6 +38,16 @@
       "204": {
         "description": "[no content](https://jsonapi.org/format/#crud-deleting-responses-204)"
       },
+      "400": {
+        "content": {
+          "application/vnd.api+json": {
+            "schema": {
+              "$ref": "#/components/schemas/failure"
+            }
+          }
+        },
+        "description": "bad request"
+      },
       "401": {
         "content": {
           "application/vnd.api+json": {
@@ -204,6 +214,16 @@
         },
         "description": "update/authors/{id}"
       },
+      "400": {
+        "content": {
+          "application/vnd.api+json": {
+            "schema": {
+              "$ref": "#/components/schemas/failure"
+            }
+          }
+        },
+        "description": "bad request"
+      },
       "401": {
         "content": {
           "application/vnd.api+json": {
@@ -349,6 +369,16 @@
         },
         "description": "retrieve/authors/{id}/"
       },
+      "400": {
+        "content": {
+          "application/vnd.api+json": {
+            "schema": {
+              "$ref": "#/components/schemas/failure"
+            }
+          }
+        },
+        "description": "bad request"
+      },
       "401": {
         "content": {
           "application/vnd.api+json": {
@@ -486,6 +516,16 @@
         },
         "description": "List/authors/"
       },
+      "400": {
+        "content": {
+          "application/vnd.api+json": {
+            "schema": {
+              "$ref": "#/components/schemas/failure"
+            }
+          }
+        },
+        "description": "bad request"
+      },
       "401": {
         "content": {
           "application/vnd.api+json": {
@@ -664,6 +704,16 @@
       "204": {
         "description": "[Created](https://jsonapi.org/format/#crud-creating-responses-204) with the supplied `id`. No other changes from what was POSTed."
       },
+      "400": {
+        "content": {
+          "application/vnd.api+json": {
+            "schema": {
+              "$ref": "#/components/schemas/failure"
+            }
+          }
+        },
+        "description": "bad request"
+      },
       "401": {
         "content": {
           "application/vnd.api+json": {
@@ -1231,6 +1281,16 @@
               },
               "description": "List/authors/"
             },
+            "400": {
+              "content": {
+                "application/vnd.api+json": {
+                  "schema": {
+                    "$ref": "#/components/schemas/failure"
+                  }
+                }
+              },
+              "description": "bad request"
+            },
             "401": {
               "content": {
                 "application/vnd.api+json": {

rest_framework_json_api/schemas/openapi.py

@@ -779,6 +779,7 @@ def _add_generic_failure_responses(self, operation):
         Add generic failure response(s) to operation
         """
         for code, reason in [
+            ("400", "bad request"),
             ("401", "not authorized"),
         ]:
             operation["responses"][code] = self._failure_response(reason)